Users of portable devices have a desire for optical devices that exhibit a high resolution and a small size and have various photographing functions (e.g., optical zoom-in/zoom-out, auto-focusing (AF), and anti-handshaking or optical image stabilization (OIS) functions). Although these photographing functions may be implemented by combining several lenses and directly moving the lenses, the size of an optical device may be increased when the number of lenses is increased. Auto-focusing and anti-handshaking functions are implemented by moving or tilting several lens modules, which are fixed to a lens holder so as to be aligned with the optical axis, along the optical axis, or in the direction perpendicular to the optical axis, and a separate lens-driving device is used to drive the lens modules. However, the lens-driving device exhibits high power consumption, and a glass cover needs to be separately added to the camera module in order to protect the lens drive device, thereby increasing the overall thickness.